Indian Journal of Urology
UROSCAN
Year
: 2006  |  Volume : 22  |  Issue : 2  |  Page : 160--161

Stop smoking to get a male child


Rajeev Kumar, Gagan Gautam 
 Department of Urology, All India Institute of Medical Sciences, New Delhi - 110 002, India

Correspondence Address:
Rajeev Kumar
Department of Urology, All India Institute of Medical Sciences, New Delhi - 110 002
India




How to cite this article:
Kumar R, Gautam G. Stop smoking to get a male child.Indian J Urol 2006;22:160-161


How to cite this URL:
Kumar R, Gautam G. Stop smoking to get a male child. Indian J Urol [serial online] 2006 [cited 2022 May 20 ];22:160-161
Available from: https://www.indianjurol.com/text.asp?2006/22/2/160/26580


Full Text

 Summary



There is evidence that the male: female ratio has declined in many industrialized countries in the last decade. Although the reason for this trend is not fully understood, exposure to toxic environmental agents, including smoking and stress, has been pointed out as possible causes. The authors performed a retrospective study to evaluate the effect of parental smoking habits on the sex ratio of ejaculated sperms before and after swim up treatment and on the embryos using pre-implantation genetic diagnosis (PGD), 3 days after fertilization by intracytoplasmic sperm injection (ICSI).

The authors retrospectively assessed smoking habits of 56 couples who had undergone ICSI and PGD at their center. The groups were classified based on the smoking pattern of the male into non-smokers, smokers (1-19 cigarettes per day) and heavy smokers (> 19 cigarettes per day). Female smokers were also similarly classified to evaluate effect on the embryo. Fluorescence in-situ hybridization (FISH) was performed on ejaculated sperm samples before and after swim-up technique, to analyze chromosomes X and Y. On day 3, embryos were also analyzed.

The ejaculated sperms had a normal Y:X ratio in all three groups of men. However, in heavy smoking donors, a statistically significant decrease of Y: X ratio was observed after swim-up. Similarly, in male heavy smokers, the XY: XX embryo ratio was decreased, compared with non-smokers (22:47 versus 80:71; P = 0.0057). The smoking condition of the female partner had no significant effect on embryo XY: XX ratio.

This authors concluded that: (i) the Y: X ratio of ejaculated sperms is unchanged between non-smoking and heavy smoking patients; (ii) there is a significant increase in X-bearing sperms after processing in heavy smokers; and (iii) the number female embryos is significantly increased in heavy male smokers.

 Comments



It is generally accepted that there is an equal number of female and male conceptions, but the number of male births (secondary sex ratio) is marginally higher at 105 to 100.[1] However, the females have a higher first year survival and the net ratio at about the age of one year is equal. The sex ratio at birth (female to male) in India is 933. This ratio declines to 927 in the first 5 years of life.[2] In a recent publication on the declining sex ratio in some parts of India, Jha et al[3] reported that for first order births, there were 871 females for every 1000 males born. For second order births, if the first child was a female, the birth ratio had a deficit of a whopping 25%. Delhi and Punjab had sex ratios of 631 and 614 only, respectively. The clearly 'unnatural' reason for this is apparent, because if the first child was a male, the sex ratio was nearly equal.

This data supports the long held belief that there is an overwhelming preference for male children among the Indian population. This desire has been fuelled by a number of medical advancements that have made such selections possible before birth. The most common technique was the prenatal ultrasound which could detect the sex of the fetus fairly accurately and led to sex-selective abortions. The pre-natal diagnostic techniques (regulation and prevention of misuse) act 1994, outlawed all such practices, but the demand has been so great that clinicians started using alternative techniques to bypass both the word and spirit of the act. One of the ways of doing this was using 'male' sperms during in-vitro fertilization. Sperm preparation using the swim-up method was supposed to selectively separate Y bearing sperms in the supernatant and this was used for insemination while discarding the sediment. There have been numerous publications supporting and refuting this hypothesis.[4],[5],[6],[7] The uncertainties associated with this technique have led to the use of further refined and advanced techniques such as pre-implantation genetic diagnosis (PGD) which involves an actual biopsy of the embryo and is therefore nearly fool-proof. The technique has become well established and there are even web sites (www.sexselection.net, www. choosethegenderofyourbaby.com) that offer the facility.

There can be no argument in support of such selections, except in cases of sex-linked genetically transmitted diseases. While the ideal approach would be elimination of such gender discrimination, this paper by Viloria et al, could help use this craving for a male child achieve another public health objective of lowering tobacco consumption. They have noted that heavy smoking by the male partner leads to a decline in the number of Y bearing sperms after swim up and also in the number of male embryos conceived. This could be used to advise all prospective parents that if they want a male child, the only acceptable method is to quit smoking.

References

1http://en.wikipedia.org/wiki/Sex_ratio, Accessed May 18, 2006
2http://www.censusindia.net/results/resultsmain.html, Accessed May 18, 2006.
3Jha P, Kumar R, Vasa P, Dhingra N, Thiruchelvam D, Moineddin R. Low male-to-female sex ratio of children born in India: National survey of 11 million households. Lancet 2006;367:211-8.
4Check JH, Katsoff D. A prospective study to evaluate the efficacy of modified swim-up preparation for male sex selection. Hum Reprod 1993;8:211-4.
5Khatamee MA, Horn SR, Weseley A, Farooq T, Jaffe SB, Jewelewicz R. A controlled study for gender selection using swim-up separation. Gynecol Obstet Invest 1999;48:7-13.
6Samura O, Miharu N, He H, Okamoto E, Ohama K. Assessment of sex chromosome ratio and aneuploidy rate in motile spermatozoa selected by three different methods. Hum Reprod 1997;12:2437-42.
7Lobel SM, Pomponio RJ, Mutter GL. The sex ratio of normal and manipulated human sperm quantitated by the polymerase chain reaction. Fertil Steril 1993;59:387-92.